An Airbus Defence and Space satellite image courtesy of Stratfor shows Russian combat aircraft stationed at the Bassel al Assad air base near the Syrian town of Latakia

An Airbus Defence and Space satellite image courtesy of Stratfor, a geopolitical intelligence and advisory firm in Austin, Texas, shows at least 16 Russian combat aircraft stationed at the Bassel al Assad air base near the Syrian town of Latakia September 20, 2015. Russia has started flying drone aircraft on surveillance missions in Syria, U.S. officials said on Monday, in what appeared to be Moscow’s first military air operations inside the country since staging a rapid buildup at a Syrian air base. Mandatory Credit REUTERS/www.Stratfor.com/Airbus Defense and Space/Handout via Reuters ATTENTION EDITORS – THIS PICTURE WAS PROVIDED BY A THIRD PARTY. REUTERS IS UNABLE TO INDEPENDENTLY VERIFY THE AUTHENTICITY, CONTENT, LOCATION OR DATE OF THIS IMAGE. THIS PICTURE IS DISTRIBUTED EXACTLY AS RECEIVED BY REUTERS, AS A SERVICE TO CLIENTS. FOR EDITORIAL USE ONLY. NOT FOR SALE FOR MARKETING OR ADVERTISING CAMPAIGNS. NO SALES. NO ARCHIVES. MANDATORY CREDIT